In the present state of the art devices for electrotherapy are known which are based on the application of high frequency currents aimed at producing hyperthermia effects, i.e., local heating of the cell tissues of determined parts of the body, affected by neoplasias and analogous ailments.
A pair of symmetrical and metallic plates are used in one of the known hyperthermia devices for electrotherapy, acting the body of the patient as a resistor element, whose plates or electrodes are generally connected to the transformer of the output stage of the corresponding circuit.
This type of device has been improved by the subject matter of Patent ES-2102301 (P9400929), held by the common assignee of the present application which discloses an active metallic electrode which shows a more reduced dimension than the return electrode also constituted by a metallic plate, the dimensional difference between the two electrodes, arranged one in front of the other on the two sides of the body region to be treated, determines an effect of increased impedance that, combined with the frequency potency amplifier generator, with adequate output impedance, determines the necessary increase in the treatment temperature at the local level.
In these devices, given their functioning characteristics and the nature of their operation, usually, in the known types of oscillation generators for electrotherapy, the working potency must be reduced to a minimum when applying the electrode to the pertinent body area and when separating the electrode itself at the end of the treatment operation. Sparks and/or burns on the treated areas can also be caused by the known devices for electrotherapy.